Potassium Carbonate → (S,E)-1-tert-butyl 2-methyl 4-(methoxymethylene)pyrrolidine-1,2-dicarboxylate

HRID 1504335Notes

Reaction equation

HRID 1504335 reaction equation
[C:1](=[O:4])([O-])[O-].[K+].[K+].O=[C:8]1[CH2:12][N:11]([C:13]([O:15][C:16]([CH3:19])([CH3:18])[CH3:17])=[O:14])[C@H:10]([C:20]([O:22][CH3:23])=[O:21])[CH2:9]1.[N+](=[C:26](P(=O)(OC)OC)C(=O)C)=[N-]>CO>[CH3:26][O:4]/[CH:1]=[C:8]1\[CH2:9][C@@H:10]([C:20]([O:22][CH3:23])=[O:21])[N:11]([C:13]([O:15][C:16]([CH3:19])([CH3:18])[CH3:17])=[O:14])[CH2:12]\1

Participants

5

Reactant 3

HCID 11430Potassium CarbonateHCID 109884851-tert-butyl 2-methyl (2S)-4-oxopyrrolidine-1,2-dicarboxylateHCID 136023029(1E)-1-diazo-1-dimethoxyphosphorylpropan-2-one

Product 1

HCID 86682810(S,E)-1-tert-butyl 2-methyl 4-(methoxymethylene)pyrrolidine-1,2-dicarboxylateYield 3,057.4%

Reagents, catalysts & solvents 1

HCID 887MethanolSolvent

Procedure

Potassium carbonate (200 g, 2.17 mmol) was added to a solution of (S)-1-tert-butyl 2-methyl 4-oxopyrrolidine-1,2-dicarboxylate (88 g, 362 mmol) and dimethyl 1-diazo-2-oxopropylphosphonate (200 g, 1.04 mol) in methanol (1 L) at 0° C. and the reaction mixture was stirred at RT overnight, quenched, concentrated, poured into water, extracted with DCM, and purified by column chromatography to provide the title intermediate (18 g, 17% yield) as a yellow oil. 1H NMR (400 MHz, CDCl3): δ(ppm) 1.406-1.457 (d, 9H, J=20.4 Hz), 2.502-2.520 (m, 1H), 2.601-2.631 (m, 1H), 2.720-2.782 (m, 1H), 3.578 (s, 3H), 3.707 (s, 3H), 3.952-3.983 (m, 1H), 4.302-4.375 (m, 1H), 4.471-4.490 (m, 1H), 5.810-5.968 (m, 1H).

Workup

  1. customquenched
  2. concentrationconcentrated
  3. additionpoured into water
  4. extractionextracted with DCM
  5. custompurified by column chromatography

Sources & evidence

ORD record
ord-e3281c51be3b4cfbb623095dafb78de6
Source dataset
uspto-grants-2015_12
Patent number
US09212168B2

Reaction notes

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